Change a Primary Key from Nonclustered to Clustered

Question

Suppose I have an SQL Server 2005 table, TableX, with 2 indexes on it:

PK_TableX = PRIMARY KEY NONCLUSTERED on FieldA
IX_TableX_FieldB = CLUSTERED on Fiel

Answer 1

1) Drop the existing clustered index first (IX_TableX_FieldB):

   DROP INDEX TableX.IX_TableX_FieldB

2) Create a (temporary) UNIQUE constraint on the unique fields referenced in the primary key

    ALTER TABLE TableX
    ADD CONSTRAINT UQ_TableX UNIQUE(FieldA)

3) Drop the PRIMARY KEY

    ALTER TABLE TableX
    DROP CONSTRAINT PK_TableX

4) Recreate the PRIMARY KEY as CLUSTERED

   ALTER TABLE TableX
   ADD CONSTRAINT PK_TableX PRIMARY KEY CLUSTERED(FieldA)

5) Drop the temporary UNIQUE constraint

   ALTER TABLE TableX
   DROP CONSTRAINT UQ_TableX

6) Add the IX_TableX_FieldB back on as NONCLUSTERED

   CREATE NONCLUSTERED INDEX IX_TableX_FieldB ON TableX(FieldB)